1. Field of the Invention
The present disclosure relates to an illumination light communication apparatus which superimposes a communication signal onto illumination light by modulating a light intensity of the illumination light, and an illumination light communication system using the illumination light communication apparatus.
2. Description of the Related Art
Lighting apparatuses provided with visible light communication functions for transmitting communication signals using illumination light have conventionally been known. As one type of the above-described lighting apparatuses, a lighting system is known which includes: a lighting apparatus that transmits own address data to a predetermined region via a visible light communication scheme; and a terminal which receives the address data (see, for example, Patent Literature (PTL) 1). A visible light communication system is known which includes a lighting apparatus that transmits and receives location information or the like to and from a mobile terminal including a visible light communication module via a visible light communication (see, for example, PTL 2).
In addition, a location detecting system is known which transmits and receives own location information via several communication tools including not only the visible light communication but also IMES (Indoor Messaging System) communication, for example (see, for example, PTL 3). The visible light communication using a lighting apparatus is suitable for identifying location information because the communication can be established only in a range irradiated with illumination light. However, the illumination light does not always stay on. For that reason, as in the above-described PTL 3, it is possible to surely acquire accurate location information of a communication terminal by combining a plurality of communication tools.